Review log files and disk space

[benloh]

Now that the nc-multiplex is relatively stable, and we have extensive logging, we need to remember to:

1. Periodically check disk space to make sure log files aren't eating up all the disk space
2. Periodically clear or archive log files

[benloh]

@jdanish Assigning this to you for now since you'll have a better sense of how often the server is used.

We should probably introduce log rotation and archiving as features.

Use df -h on the droplet console to check disk space in human readable form